9. Subject Considerations

9.1 Clinical trial subject recruitment: Are digital advertisements (including social media streams such as TikTok) allowed and, if so, what regulations govern them?

The ethics committee has the responsibility of approving the recruitment mechanism. It is up to the committee to decide what is allowed.

9.2 Vulnerable Subjects

In clinical trials, when the potential participant is vulnerable socially, culturally, educationally, or economically, an independent witness of the investigator or his team must participate in the informed consent process and must sign and date the consent form as proof of his participation.

When planning research on communities or groups of people linked for ethnic, geographical, social, or common interests, the agreement of a community representative should be sought, for example, by including him or her in the REC assessment. The representative should be chosen according to the nature and traditions of the community, and researchers and members of CEI should ensure that these people unequivocally represent the interests of the community. In communities where collective decisions are often made, researchers should consider obtaining approval from community leaders prior to individual decisions.

Researchers should identify those individuals or groups in vulnerable situations to implement special protection mechanisms for them.

A. Individuals unable to give consent

They are underage individuals and people with transient, fluctuating, or permanent mental disorders. Research with these groups is only warranted when:

• The knowledge expected to be gained from the research is sufficiently relevant in relation to the foreseeable risks.
• The risks of an observational study are only slightly greater than those associated with routine medical and psychological examinations of such persons in the condition being investigated.
• The risks of an experimental investigation are similar to those of interventions that usually individuals receive for the condition being investigated.
• The REC has specialists or consult experts in those particular groups.

B. Cultural, educational, social, or economic vulnerability

Participation in clinical trials of populations vulnerable for cultural, educational, social, or economic reasons, such as ethnic minorities or people who are illiterate, subordinate, refugees, destitute, or with unmet basic needs, requires additional protections. As a guarantee that the particular values and interests of the potentially vulnerable participant were respected, consent should be obtained in the presence of an independent witness of the researcher and his team. As a guideline, observation of one or more of the following indicators can be used to establish the need for this additional protection:

• Unemployment or informal or unstable work of the main breadwinner.
• Homeless or precarious housing (hotel or boarding house, tenancy, house taken, or construction not intended for housing) or housing located in unfavorable areas (village or informal settlement).
• Lack of social security coverage (social work or prepaid).
• Illiteracy or incomplete primary study.
• Indigenous people or people belonging to an ethnic group whose primary language is not Spanish.
• Refugee or displaced status.

C. Participation of women of reproductive age or pregnant women

The possibility of becoming pregnant during the study should not, by itself, be used as a reason to exclude or limit the participation of women of reproductive age. The requirements to minimize the risks include informing potential participants in detail about the risks to the pregnancy and the fetus and guaranteeing them access to pregnancy tests and effective contraceptive methods before and throughout the research. 

In the case of pregnant women, in addition to the requirement to provide detailed information about the risks to them and the fetus, it is recommended that consent be obtained from the pregnant woman's partner, if applicable. Research in this population can only be conducted if it is relevant to health problems related to pregnancy and the product of conception, and if it is adequately supported by previous animal experiments, particularly to establish the risks of teratogenesis and mutagenesis.

9.3 Pediatrics (including whether consent from a single parent is sufficient vs. requiring both parents to sign)

In general, the voluntary cooperation or consent of a minor to participate in an investigation should be sought, after providing the information appropriate to his or her degree of maturity.

Children who are too immature to nod with understanding may be able to express a 'deliberate objection' (i.e., an expression of disapproval or denial of the proposed procedure) which should be respected unless the child needs treatment not available outside the context of the research, the intervention under study implies a likelihood of therapeutic benefit, and there is no accepted alternative therapy.

The REC must determine the age from which the minor's assent will be required, depending on the characteristics of each study.

Where consent cannot be provided by the child, parental consent must be obtained from at least one parent.

9.4 Financial Disclosures

At times, it can be difficult to clearly distinguish between a legitimate motivation and the offer of excessive or inappropriate encouragement. The potential and actual benefits of research (e.g., gaining knowledge) are appropriate incentives. Similarly, the promise of compensation and medical care for injury or loss of income should not be considered an inducement to participate.

On the other hand, those who lack basic goods or adequate health care are particularly exposed to an undue incentive when offered goods, services, or cash payments for their participation and therefore require a guarantee of free and voluntary consent through the presence of an independent witness in the process of obtaining it. In research, without potential health benefits for participants (e.g., in the case of healthy volunteers), participants may receive a payment, the type or amount of which must be approved by the REC.

9.5 ICF translations – Are Certificates Required?

There is no requirement for certificates. However, the following must be complied with:

The oral and written information provided to the potential participant or his/her representative must be presented in a clear, precise, complete, truthful manner, in practical language appropriate to his/her understanding, expressed in the primary language of the consenter and without including any expression that may lead one to believe that the participant lacks or waives any of his/her rights or that the researcher, Institution, or sponsor is released from their responsibilities by signing the consent. The written document should guide the verbal explanation.

9.6 Subject Compensation: Is there a need for a local sponsor to be listed on the insurance certificate, the insurance certificate to cover the duration of the study, and specific minimum amounts of coverage to be specified, both for individual events occurring and in aggregate?

Compensation for accidental injuries

If an investigation causes harm, the sponsoring entity must compensate the injured party in an appropriate manner according to the type of damage.

Pecuniary losses must be repaired promptly. In other cases, it may be difficult to determine appropriate compensation. Violation of confidentiality or indiscriminate publication of the findings of a study, causing the disrepute of an individual or group, may be difficult to remedy, and the REC should define what compensation is appropriate in such cases.